Teflon producer DuPont, now Chemours, has known for 30 years that they are seriously polluting the groundwater in Dordrecht with large amounts of toxic and carcinogenic PFAS, Zembla reports based on confidential documents from the chemical group. The documents showed DuPont had serious concerns about contaminating the drinking water with PFAS in the early 1990s. PFAS pollution is still a problem in Doredrecht.